Is it really that big of a deal? Performing a coup de grace without any type of feat takes a full-round action that provokes an attack of opportunity. So unless I am within a 5-foot step I cant even do it in the same round. And since you get a save every round on your turn, the percentage of kill potential is significantly reduced. Also, even without the coup de grace mechanic, being paralyzed in combat is pretty much a death sentence anyway. Then the whole time I'm taking attacks from other hostile creatures in the area from the attack of opportunity. Then finally, hold person only works on humanoids. I dunno anything about the games yall are playing, but a majority of the things you will just randomly encounter aren't even affected by the spell. Though I am a fan of the combo, it is so conditional. I personally think that if your players manage to hit it on someone, they should be rewarded rather than punished. And if you're doing it on your players... They should be more careful. :D